Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Debt securities, available for sale, cost	$ 3,585.9	$ 2,678.1
Debt securities, trading, cost	1,199.9	1,630.1
Debt securities, available for sale, allowance for credit losses	0.0	0.0
Short-term investments, cost	595.3	984.5
Other long-term investments, cost	372.9	392.0
Related party investments at fair value	199.1	201.2
Equity securities, trading, cost	$ 1.6	$ 1.8
Common share, shares issued (in shares)	162,367,173	162,177,653
Common share, shares outstanding (in shares)	162,367,173	162,177,653
Series B preference shares
Preference shares, par value (in dollars per share)	$ 0.10	$ 0.10
Preference shares, shares authorized (in shares)	8,000,000	8,000,000
Preference shares, shares issued (in shares)	8,000,000	8,000,000

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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